It is conventional during the manufacture of an alternator to form the slip rings directly on a projecting part of the alternator shaft.
Another known technique consists in making the slip ring unit, or collector, as a separate component, using for example a method whereby the body of the component is moulded on to its electrically conductive parts. The slip ring unit is subsequently fitted on to the shaft of the alternator, typically by force fitting.
Such a slip ring unit, formed in the known way as a separate component, comprises a generally cylindrical first body portion which includes two slip rings at its outer surface, a second body portion which includes two connecting elements for making electrical connection with the wire ends of the winding wires of the alternator, and an intermediate body portion which provides electrical and mechanical connection between the first and second body portions. This intermediate body portion is in the form of two branches, each of which comprises a conductive portion for providing a link between a corresponding slip ring and a connecting element which is embedded in the insulating material of the body.